The purpose of the proposed study is to: 1) advance understanding about the relationship between stress, coping and athletic injuries, and 2) identify subsets of individuals at increased risk of injury because of psychosocial characteristics which interfere with optimal and safe performance. We aim to assess whether: 1) stressors exert their influence over long or relatively short periods of time, 2) the appraisal of sports related events as stressful is more salient that other types of events, 3) the stress-injury relationship is moderated by different coping strategies, sensation seeking, varying emotional response to the appraisal of stressful situations, social support, 4) injured cadets are more likely than uninjured to experience high competitive anxiety, disrupted concentration and attention, increased muscle tension and disruption of sleep. We propose to carry out this study at the United States Military Academy (USMA). USMA offers a unique opportunity to study these issues because of a highly controlled and uniform environment, the centralized provision and recording of health care, a high frequency of injuries, the ability to collect self-report data directly through terminals at each cadet's desk, and the deep interest the military has in injury prevention. We also propose to carry out one aspect of this study at the University of Florida (U.FL) utilizing varsity football players as a comparison group. The design of the proposed project has four components: 1) a prospective study of stressors and background characteristics in two periods of time: upon entry to USMA, and at the beginning of the sophomore year, and injuries in the subsequent semesters; 2) a case-control study of injured cadets matched on athletic exposure to uninjured cadets; 3) a prospective study of perceived stress and response to stress measured on a daily basis over one three week period of time each semester at USMA; and 4) a prospective study of stressors and background characteristics of the U.F1 athletes and injuries in the 1994 football season. If we are able to demonstrate a clear relationship between stress and injuries, delineate time periods of greatest risk, identify mechanisms that link stress to injuries, identify individuals at highest risk and indicate that the findings are replicable in several settings, we could make a substantial contribution to knowledge about the injury process and to reducing morbidity from athletic activities.